yes, i have/had the same problem with my specialized command post, i did manage to sort it, funnily enough when i changed a kinked xtr outer cable for a cheap clarkes one from halfrauds!!! think it must be a slightly bigger bore, i just make sure its well oiled and so far its been ok, however if i forget to clean the bike (tuttut) then it takes a bit of fettling! i think the best bet is prob a reverb, however whilst mine is still ok it will have to wait!
Matt, yes totally understand, didnt really think of price, thought issue was post diameter, my fault for not reading properly!